Answer:
100%
Step-by-step explanation:
Perimeter of first garden is given by 2(l+w) where l is length and w is width
Perimeter=2(5+3)=16
The dimensions of second rectangle is doubled hence 10 ft by 6 ft
Perimeter=2(10+6)=32
Change in area will be 32-16=16
Percentage change in area is 16/16*100=100%